4 Replies Latest reply on Oct 10, 2015 1:11 PM by JacobT_81

    BCM20736S slow and inconsistent operation of the fast timer callback

      I am running a simple application on the BCM20736S, and I am hoping for a fast startup. I am not using BLE at all in my application for  now. It is a long story, but for the moment I am just using the fast timer callback, I2C, PUART and a some simple logic in the code.

       

      My problem is that I see slow and inconsistent operation of the fast timer callback, especially at startup. It gets called a few times a second, sometimes once every few seconds. The rate is currently set to 10ms, which should give me 80Hz call rate for the best case. Here is my debug output where I simply print a counter value from the fast timer interrupt.

       

      Hours:Minutes:Seconds - Counter

      15:30:49 - 29

      15:30:49 - 30

      15:30:49 - 31

      15:30:49 - 32

      15:30:50 - 33

      15:30:53 - 34

      15:30:53 - 35

      15:30:54 - 36

      15:30:54 - 37

      15:30:54 - 38

      15:30:55 - 39

      15:30:55 - 40

      15:30:55 - 41

      15:31:08 - 42

       

      After I run for awhile, this slow behavior will sometimes go away, and sometimes not. When it is working well, I see a consistent 80Hz rate of timer callbacks. I am hoping for this behavior all the time.

       

      My questions are:

      1. Is there a way to turn off the BLE tasks (or other processor hungry tasks) that are keeping the fast timer callback from running? I have a simple application, so do not need BLE at this point.

       

      2. Is this normal behavior for this part? Is there a way to improve it?

       

      Thanks in advance,

           Aaron